I think the default written into the code is basically irrelevant, as we will want to specify the key location in the config.js file anyway. I'm personally ambivalent towards the two options of scripting it in during the BI process versus the core scripts. Offhand, I would say that it's better to put it in the core scripts, so as to avoid needing a "dev" BI script and a "production" BI script. Although it may prove necessary to have two.